Traditionally, an information system is known in which a screen is built in a table top and an image is projected by a projector from underneath (see Patent Reference 1). With this information system, many users around the table can watch the image at the same time.
Patent Reference 1: JP-A-2001-75733
However, the information system described in the Patent Reference 1 allows the users only to watch an image shown on the table but not to separately listen to the sound relating to the image (such as voice, music, and signal sound; hereinafter the same) which each user wants to listening to, when he/she wants to listen to it. Of course, it is proposed in the Patent Reference 1 to output sound along with the image, but audio information is carried from a speaker to all the users around the table, and all the users always listen to the same sound at one time.
More specifically, audio information support has not been implemented yet which separately responds to individual users watching an image to acquire audio information that a single user wants now and here.